Non-chemical rocket engines are generally accelerated to emit: ____.
A. Hydrogen
B. Helium
C. Argon
D. Xenon
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The propellant feeding system of liquid rocket engine includes: ____.
A. Vacuum system
B. Pressure-feed system
C. Gravity transporting system
D. Pump-feed system
About "Minuteman III", which of following are true? ____.
A. It is intercontinental missile
B. It is ballistic missile
C. The third stage adopts solid rocket engine
D. It has a firing range of more than 12,000 kilometers
The thrust direction of rocket engine could be control by: ____.
A. Valve
B. Secondary injection technology
C. Swinging nozzle
D. Jetavator
Solid rocket engines generally are using on: ____.
A. Sounding rockets
B. Air-to-air missiles
C. Rocket boosters
D. Main engine of space shuttle
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